Ceramic Materials Commons^™

A Study In The Advanced Manufacturing Of Full Solids Oxide Fuel Cells (Sofcs) Via Aerosol Deposition (Ad) Methods With Macro- And Microstructural Defect Characterization, Davis A. Warmuth

Graduate Theses, Dissertations, and Problem Reports (ETD)

The goal of this work is to 3D print a full SOFC layer-by-layer using aerosol deposition (AD) at a resolution of 5 μm. To achieve this goal, several studies were undertaken to develop and optimize an AD system to use ceramic inks. A 130 kHz AD system was developed with 4 material pumps to allow for depositions of individual compositions of the in-situ mixture of multiple solutions to allow for the fabrication of functional gradients in three dimensions. This system was then programmed to deposit air electrode layers containing different material ratios and porous microstructures, comparing their electrochemical performance to …

Bridging Physics-Based Modeling And Machine Learning To Predict Material Behavior: Applications In Fatigue Crack Growth And Dielectric Property Characterization, Ansan Pokharel

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation integrates physics-based modeling with machine learning (ML) to predict how materials behave under complex thermal and mechanical conditions. A key innovation of this work is the use of finite element analysis (FEA) to supplement experimental data. This approach creates more diverse and representative synthetic datasets, helping to reduce the limitations and biases that arise when training ML models solely on experimental measurements. The research focuses on two applications: improving the prediction of fatigue properties in superalloys and estimating temperature-dependent, high-frequency dielectric properties relevant to microwave-based chemical processing.

In the first study, low-cycle fatigue experiments were performed on the …

Microwave-Assisted Reduction Of Critical Metal Oxides From E-Waste Mixture, Kurundu Shavinka Jayasekera

Graduate Theses, Dissertations, and Problem Reports (ETD)

The efficient recovery of critical metals such as tantalum (Ta), manganese (Mn), gallium (Ga), and indium (In) from electronic waste (e-waste) is essential for resource sustainability and environmental protection. This research uses microwave-assisted treatment to investigate the carbothermal reduction of these four specific metals from their oxides in a simulated e-waste mixture, with carbon black serving as both a microwave coupling and reduction agent. Microwave processing is used specifically because it offers a rapid and energy-efficient alternative to conventional thermal methods, with the benefits of intrinsic heating and selective heating of materials. The first experiments centered on understanding the effects …

La2nio4+Δ-Based Solid Oxide Electrolysis Cell (Soecs) Electrodes Enhanced With Complex Perovskite Nanocatalyst Processed By Surfactant-Enabled Infiltration, Cole Samuel Klemstine

Graduate Theses, Dissertations, and Problem Reports (ETD)

As the world seeks to reduce its reliance on hydrocarbons, the demand for sustainable hydrogen production methods has become increasingly critical. Hydrogen is a versatile energy carrier that can be produced from various sources, including water, natural gas, and biomass. Replacing the burning of hydrocarbons with hydrogen could significantly reduce greenhouse gas emissions, contributing to global climate goals like those set by the US H2NEW program. The joint technologies of solid oxide fuel and electrolysis cells present the ability to both produce and process clean hydrogen to meet these goals. Development into solid oxide fuel cells has been met with …

Novel Design And Fabrication Of A High-Speed Transient Heat Flux Sensor For Application To Rotating Detonation Engines, Zachary Todd Tallman

Graduate Theses, Dissertations, and Problem Reports (ETD)

Rotating detonation engine (RDE) combustion systems have been a topic of interest in the pressure gain combustion community for their benefits over traditional gas turbine engine combustors. However, cooling requirements for these engines are significantly higher and less predictable than those of non-detonating engines. To understand and quantify the high-speed heat transfer dynamics within an RDE, a novel high-frequency heat flux sensor is presented. This study aims to design a robust, single-sided sensor that can withstand the high temperature and harsh environment of an RDE for extended durations. Screen printing is used to deposit a layered, platinum-yttria-stabilized zirconia (YSZ) film …

Far-Field Passive Wireless Sensors Composed Of Electroceramic Materials For Harsh Environment Applications, Kevin M. Tennant

Graduate Theses, Dissertations, and Problem Reports (ETD)

The demand for high temperature sensing technologies in industrial applications has been steadily increasing, driven by the need for precise monitoring and control in extreme environments. This thesis presents an investigation into the development and optimization of passive wireless sensors for high temperature sensing applications. The research focuses on overcoming the challenges associated with traditional sensing methods by leveraging passive wireless sensor technology, offering advantages such as reduced complexity, improved reliability, and enhanced flexibility.

A passive wireless high temperature sensor for far-field applications was developed for stable temperature sensing up to 1000 °C. The goal is to leverage the properties …

Processing, Stability, And High-Temperature Properties Of Doped Lacro3-Based Refractory Ceramics And Composites For Harsh Environments Sensing Applications, Javier A. Mena

Graduate Theses, Dissertations, and Problem Reports (ETD)

In order to test and monitor the operational stability and conditions of various energy, transportation, and manufacturing systems and their components, accurate sensors capable of operating at temperatures over 1000 °C in various environments for long durations are required. In addition, many of these harsh environmental systems do not permit sensors to be directly inserted into the environment, so the sensors need to be embedded into the surrounding support or thermal protective materials. Some technological and industrial applications that require the use of harsh environment conditions sensing include nuclear and chemical reactors, jet engines, heavyduty gas turbines, rotating bearings in …

Passive Wireless Corrosion And Temperature Detection In High-Temperature Environments, Noah Lane Strader

Graduate Theses, Dissertations, and Problem Reports (ETD)

This work focuses on the theory and development of LC sensors for high temperature and corrosion measurement for stainless steel and copper surfaces with power industry and general corrosion detection applications. The LC resonators were fabricated via screen printing an Ag inductor on an alumina substrate. The LC design was modeled using the ANSYS HFSS modeling package. The LC passive wireless sensors operate with resonant frequencies centered at 85-110 MHz. The wireless response of the LC sensor was interrogated and received by a radio frequency signal generator and spectrum analyzer at temperatures from 50-800 °C for copper ground planes and …

Manganese-Based A-Site High-Entropy Perovskite Oxides For Solar Thermochemical Hydrogen Production, Cijie Liu

Graduate Theses, Dissertations, and Problem Reports (ETD)

Non-stoichiometric perovskite oxides have been studied as a new family of redox oxides for solar thermochemical hydrogen (STCH) production owing to their favourable thermodynamic properties. However, conventional perovskite oxides suffer from limited phase stability and kinetic properties, and poor cyclability. Here, we report a strategy of introducing A-site multi-principal-component mixing to develop a high-entropy perovskite oxide, (La_1/6Pr_1/6Nd_1/6Gd_1/6Sr_1/6Ba_1/6)MnO₃ (LPNGSB_Mn), which shows desirable thermodynamic and kinetics properties as well as excellent phase stability and cycling durability. LPNGSB_Mn exhibits enhanced hydrogen production (~77.5 mmol moloxide^–1) compared to (La …

System Analysis Of An Internal Combustion Engine (Ice) – Solid Oxide Fuel Cell (Sofc) Hybrid Cycle, Jose Javier Colon Rodriguez

Graduate Theses, Dissertations, and Problem Reports (ETD)

Due to the intermittent nature of renewable energy and the rigid operation of existing coal plants, the need for flexible power generation technology is eminent. Hybrid energy systems have shown potential for flexible, grid following dynamics while maintaining higher efficiencies. The work below focuses on the performance analysis of a proposed 100 kW pressurized Internal Combustion Engine (ICE) and Solid Oxide Fuel Cell (SOFC) hybrid system. The un-utilized fuel from the SOFC stack provided the chemical energy to operate the engine. A turbocharger was used to deliver the necessary air flow for both the stack and engine. An external reformer …

Controlling The Thermal And Electrical Properties Of Camno3-Δ Based Perovskite Ceramics, Sergio Andres Paredes Navia

Graduate Theses, Dissertations, and Problem Reports (ETD)

Most of the energy lost during the conversion process comes in the form of waste heat. The world's energy consumption loses over 60% of its energy after conversion. In order to increase the efficiency of the conversion process, it is essential to harness waste heat and reutilize this energy resource. Heat recovery technology as thermoelectric (TE) technology is one of the growing alternatives to harvest excessive amounts of energy lost as waste heat for a more efficient, safe, and sustainable future. Due to the Seebeck effect, TE materials have the potential to convert waste heat directly into electricity, improving efficiency …

Thermochemical Water-Splitting Using Novel High-Entropy Perovskite Oxides, Hector Alexis De Santiago Hernandez

Graduate Theses, Dissertations, and Problem Reports (ETD)

In this project, we designed, synthesized, and tested the transformative (La_0.8Sr_0.2)(Mn_[1-x]/3Fe_[1-x]/3Co_xAl_[1-x]/3)O₃ (0 ≤ x ≤ 1.0) high-entropy perovskite oxides (HEPOs) as redox active oxygen carriers for thermochemical hydrogen production with improved stability, kinetics, and H₂ yield. The developed HEPOs form an R3c (hexagonal) phase and were successfully synthesized using both the Pechini and solid-state reactions with the latter synthesis being the primary source for testing. These innovative perovskites demonstrated an improved kinetics with oxygen surface exchange coefficient, k, greater than 7.5 x 10^-4 cm/s, …

Modeling, Fabrication, And Characterization Of Rf-Based Passive Wireless Sensors Composed Of Refractory Semiconducting Ceramics For High Temperature Applications, Kavin Sivaneri Varadharajan Idhaiam

Graduate Theses, Dissertations, and Problem Reports (ETD)

Real-time health monitoring of high temperature systems (>500^oC) in harsh environments is necessary to prevent catastrophic events caused by structural failures, varying pressure, and chemical reactions. Conventional solid-state temperature sensors such as resistance temperature detectors (RTDs) and thermocouples are restricted by their operating environments, sensor dimensions and often require external power sources for their operation. The current work presents the research and development of RF-based passive wireless sensing technology targeting high temperatures and harsh environmental conditions. Passive wireless devices are generally classified as near-field and far-field devices based on the interrogation distance. Near-field sensors are placed at …

Carbon Monoxide Sensing Of Nickel Oxide At 1000 ℃ To 1200 ℃ For In Situ Combustion Control: Behavior, Mechanism, And Application, Yi Wang

Graduate Theses, Dissertations, and Problem Reports (ETD)

An advanced smart sensor network is essential to a combustion system, which is in favor of in situ, locally placed, and low-cost gas sensors. However, most chemical/electrochemical sensors fail to work in a combustion boiler, due to the demanding working temperatures (> 1000 ℃). This work for the first time reports a well-functioning mixed-potential type CO sensor at 1000 ℃ - 1200 ℃ using nickel oxide (NiO) as the sensing material. The influence of feed gas flow rate, electrode thickness, and porosity on sensor behavior is investigated, delivering notable and fast responses to 1000 ppm in 3% O₂: …

Improving Performance And Durability Of Intermediate Temperature Proton‐Conducting Solid Oxide Electrolysis Cells Via Materials Design And Catalyst Surface Engineering, Hanchen Tian

Graduate Theses, Dissertations, and Problem Reports (ETD)

Solid oxide steam electrolysis cell, a promising electrical-chemical conversion device for the next generation efficient hydrogen production and energy storage, has been actively studied because of their high energy conversion efficiencies and prospective applications as electrochemical reactors. After decades of research on protonic ceramic materials, remarkable advances have been made in the protonic ceramic electrochemical cells (PCECs) air electrode and electrolyte. However, the existing air electrodes are far from satisfying the requirements of practical applications, a series of issues, including the lack of active and durable electrodes, greatly limit the commercialization. To date, the systematic development of triple conducting catalysts …

Metal Supported Solid Oxide Fuel Cell Using Proton Conducting Electrolyte For Direct Ammonia Utilization, Edwin Vega Hiraldo

Graduate Theses, Dissertations, and Problem Reports (ETD)

Transportation represents about 27% of global warming greenhouse gas emissions nowadays. To reduce these emissions, fuel cell electric vehicles have been poised to be a new trend to provide zero-emission transportation. Among them, solid oxide fuel cells (SOFCs) offer efficient, clean energy, especially when powered by carbon-free fuel, such as ammonia. To enable onboard ammonia-fed SOFCs, a metal-supported, proton-conducting SOFC is investigated in this study. The metal support would provide physical robustness for thermal shock during vehicles’ quick start-up and shutdown, reduce internal temperature gradients due to the greater thermal conductivity of the metal, and enable conventional metal joining for …

Increasing The Seebeck Coefficient Of Thermoelectric Calcium Cobaltite Ceramics Through Incorporation Of Rare-Earth Elements, Andre Fabian Fernandes

Graduate Theses, Dissertations, and Problem Reports (ETD)

The demand for alternative sources of energy continues to grow, so it is essential to look for alternatives that are environmentally sustainable to minimize the environmental impact of energy generation. Projections suggest that renewables have the potential to make up over fifty percent of power generation by 2035. Studies have shown that in 2020 more than 62% of the energy produced in the US was lost, with most of this energy being in the form of waste heat. Waste heat can be utilized to improve the efficiency of power production or even power other devices. This waste heat can be …

Doping With Rare Earth Elements And Resultant Nano-Inclusions On The Electrical And Thermal Properties Of The Mis-Fit Layered Thermoelectric Oxide, Geoffroy Gauneau

Graduate Theses, Dissertations, and Problem Reports (ETD)

Thermoelectric generators produce electricity by directly converting temperature differences into electrical energy through Seebeck effect. Thermoelectric generators possess many unique features, such as having no moving part and being very reliable with a relatively long lifespan once built. They are solid-state waste heat harvesters. With various waste heat available throughout many industries, thermoelectric generators could offer economically competitive renewable energy. The current state of the art thermoelectric materials includes materials with relatively toxic elements and must work under vacuum, making them quite expensive to produce. Among the various thermoelectric materials, ceramic oxides have been proved to be more chemically stable …

Oxygen Transport Kinetics Of Surface Modified Mixed Conductor (La0.60sr0.40)0.95co0.20fe0.80o3-X As Solid Oxide Fuel Cell Cathode, Manuel Serrano Laguna

Graduate Theses, Dissertations, and Problem Reports (ETD)

The oxygen transport kinetics of the electrodes of Solid Oxide Fuel Cells (SOFC) are critical properties to achieve higher efficiencies in the cell. (La0.60Sr0.40)0.95Co0.20Fe0.80O3-x (LSCF) is a mixed ion-electron conductor material that is expected to be optimized and utilized as the cathode of the SOFC’s. The reason for LSCF to be considered as the next cathode material for SOFC is due to its high ionic and electronic conductivities, and high oxygen transport kinetics. Additionally, to the excellent properties that this material offers, it has been seen that the kinetic properties of the material can be further optimized by adding a …

Carbon Deposition On Ni/Ysz Anode Sofc For Direct Methane Steam Reforming, Haiyang Li

Graduate Theses, Dissertations, and Problem Reports (ETD)

Solid Oxide Fuel Cells (SOFCs) are electrochemical devices that produce electricity directly from oxidizing fuels. Compared to direct combustion of hydrogen to generate power, it has a big advantage in aspects from efficiency and safety when using hydrogen as the fuel of SOFCs. Hydrocarbon reforming is one of the conventional methods to convert natural gas into hydrogen. While considering the difficulty in storage and transportation of hydrogen, we can utilize the supporting materials on the anode side of SOFCs as catalyst to generate hydrogen via hydrocarbon reforming process and pour the hydrogen as fuel into the SOFC system. Ni/YSZ is …

Enhancing The Thermoelectric Performance Of Calcium Cobaltite Ca3co4o9 Through Single And Dual Elements Doping, Cesar Octavio Romo De La Cruz

Graduate Theses, Dissertations, and Problem Reports (ETD)

Worldwide energy consumption losses more than 60% of the energy after its conversion, most of these losses are in the form of waste heat. Therefore, it is a matter of utmost importance to harness waste heat and reutilize this energy source to improve the overall conversion efficiency. Thermoelectric (TE) technology is one of the rising alternatives to harvest the excessive amount of energy lost as waste heat for a better and sustainable energy future. TE materials can utilize waste heat to improve efficiency in the ever-increasing demand for energy by converting a temperature difference directly into electricity due to the …

Exsolved Nanoparticle Decorated Redox Stable Ceramic Anode Material With High Performance For Solid Oxide Fuel Cells, He Qi

Graduate Theses, Dissertations, and Problem Reports (ETD)

The solid oxide fuel cell (SOFC) is an efficient high-temperature device that can directly convert chemical energy to electrical energy. Because of its high efficiency and environmental friendliness, extensive investigations have been made worldwide in past decades. Though broadly used as the anode material for Solid-Oxide Fuel Cells, Ni-YSZ is limited in some practical applications by severe carbon deposition on Ni in hydrocarbon fuels and a significant volume change of Ni-NiO among redox cycling. In order to overcome these problems and achieve excellent performance in the redox environment, a Ni-free ceramic material La_0.5Sr_1.5Fe_1.5Mo_{0.5 …}